Process of treating india-rubber, gutta-percha, and their compositions.



flatten rates EUGEN HORNUNG AND STEFAN HANSEL, 0F VIENNA, AUSTRIA-HUNGARY.

srncrrteazrmn forming part or Letters Patent No. 657,24l0, dated $eptember 4, 1900.

Application filed May 8,1897. Serial No. 635,642. (m mmals) To all whom it may concern:

Be it known that we, EUGEN HORNUN G and STEFAN HANSEL, subjects of the Emperor of Austria-Hungary, residing at Vienna, in the Province of Lower Austria, in the Empire of Austria-Hungary, have inventedcertain new and useful Improvements in Processes of Treating India-Rubber, Gutta-Percha, and Their Compositions; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it app'ertains to make and use the same.

The invention consists in a novel process of treating rubber, gutta-percha, or compounds thereof and the product of such process.

As is well known, indie-rubber, gotta-percha, and their compositions when vulcanized contain free sulfur and become hard and brittle by the oxidizing action of the oxygen of the air upon when these bodies are exposed to high temperatures, as is the case when used, for instance, as packing for steam-distributing pipes or other steam fittings, and that when said bodies become hardened their properties are virtually destroyed.

Our invention has for its object to avoid the disadvantage referred to by the addition to the rubber or equivalent of a compound that will protect it I against oxidation or against hardening when exposed to high tem-' peratures, and whereby a product is obtained that is'absolutely free from free sulfur.

\Ve have found by experiments that it is not possible to intimately and uniformly mix gelatin or glue that is insoluble in water with india-rubber,' guttapercha, or their compounds unless the gelatin or glue is in a plastic condition, nor is it possible to obtain by the ordinary methods of vulcanizationa product that is absolutely free from free sulfur, a fact which is well known. Although the gelatin or glue when rendered insoluble in water in a well-known manner by precipitation from its solution is obtained in the form of a more or less plastic mass, it cannot be incorporated with rubber or the like on account of the water present, which when the compound is vulcanized is evaporated and results in a more or less porous body. It is therefore essential that the insoluble plastic the surfaces exposed thereto or glue or gelatin be free from water before being incorporated with the india-rubber or the like.

Inasmuch as it is very difficult to avoid the presence of free sulfur in vulcanizing rub- --ber by the usual methodsitis also necessary in order to. obtain a product that is free from such free sulfur to provide means whereby the whole of the sulfur required for vulcanization is chemically combined with the rub.- ber or the like. by mixing the insoluble gelatin or glue first with a body containing the required quantity of sulfur not in a free state, but chemically hound thereto, and to this end we use what is called vulcanized oil, and the admixture of the insoluble gelatin or glue with the oil can be materially facilitated by swelling out the oil with turpentine, benzin, or a similar volatile hydrocarbon, the compound being then dried or freed from moisture by heat,

whereby not only the water, but also the volatile hydrocarbon, it such be used, is or are evaporated, the operation of drying being conducted carefully, when the plastic com pound thus obtained can be readily and intimately mixed with the india-rubber or the like by mechanical agencies and finally subjected to heatfor the purpose of vulcanization.

What is known as vulcanized oil is an oil of the fatty series, such as linseed or poppy or another oil of the fatty series, treated with sulfur chlorid. The proportion of sulfur chlorid depends, of course, upon the nature of the product to be obtained, whether it is to be a tough or a hard prodnot. For our uses a tough product is the most advantageous, and to this end we use aboutlfifteen parts, by weight, of sulfur ehlorid to about one hundred parts of oilsay linseed-oil. Of course, as will be readily understood, the sulfur is in this case chemically bound in-the compound, so that there cannot be any free sulfur'in the final product. Of this vulcanized 'oil, preferably after swelling with a volatile hydrocarbon, we take from 0.1 to 0.5 parts, by weight, and mix it intimately with the insoluble gelatin or glue,

the compound being then dried and mixed with the india-rubber, gutta-percha, or their compositions, and finally subjected to heat,

Both these objects we attain as above set forth. The proportions of insoluble be used will depend upon the nature of the material with which they are to be incorpogutta-per'cha, or their proportion of filling rated, whether rubber, compositions and the mass they contain. I

Having thus described our invention, what we claim as new therein, and desire to secure by Letters Patent, is-

1. The process,.which consists in mixing a Vulcanized oil of latinous or glutinous substance insoluble in water, freeing the mixture from moisture, mixing therewith rubber or a compound thereof and subjecting the composition of matter to a vulcanizing temperature, for the purpose set forth.

2. The process, which consists in swellinga vulcanized oil of the fatty series with a volatile hydrocarbon, mixing the same with a gelatin or glue and vulcanized oil to,

the fatty series with a gegelatinous or glutinous substance insoluble in, water, evaporating the hydrocarbon and insoluble in Water, and a vulcaniz d oil of said compound free from water-and containin no free sulfur; subthe fatty series,

stantially as set forth.

In testimony whereof we affix our signa tures in presence of two witnesses.

EUGrEh HORNUNG; STEFAN HANSEL. Witnesses:

HARRY BELMONT, DAVID ALBIN. 

